Fasting and Health: High Blood Pressure, Metabolism, and More.

The essentials at a glance

• Buchinger therapeutic fasting is a therapeutic method, not a cure; whether it is suitable in an individual case is always determined by the medical team at the Tannerhof.
• The guidelines for fasting therapy (ÄGHE) identify its use for conditions including high blood pressure, metabolic syndrome, rheumatism, migraines, and type II diabetes mellitus.
• In a large observational study of 1,422 people fasting, blood pressure dropped significantly on average, and 84.4 percent of participants with pre-existing conditions reported an improvement.
• In the case of cancer, fasting is only considered as an adjuvant (supportive) measure in certain stages, never as a standalone treatment.
• For those on medication or with chronic illnesses, medical supervision is not an optional extra but a prerequisite — which is exactly what the fasting week at the Tannerhof is designed for.

What fasting and health are all about

Many people come to fast not just for a break, but with a specific health concern: blood pressure that has been too high for years, a metabolism that has fallen out of sync, recurring migraines, or a rheumatic condition. The underlying question is always the same: Can fasting make a difference here?

The honest, medically sound answer is: for a range of chronic and metabolic conditions, medically supervised Buchinger therapeutic fasting can have a positive impact. This is not a promise of a cure or a guarantee for individual cases, but rather an assessment established in clinical fasting therapy guidelines. At Naturhotel Tannerhof, therapeutic fasting is offered precisely within this framework: medically supervised, always tailored to the individual, and embedded in our Body Detox program. Those looking to explore the underlying health perspectives further will also find them in our Longevity at Tannerhof program and in the Therapeutic Fasting and Schlanke Tanne hub.

First, the definition that underpins everything: Buchinger therapeutic fasting is the conscious, time-limited abstinence from solid food and stimulants. Instead of solid meals, herbal tea, mild vegetable broth, freshly pressed juices, and plenty of fluids carry you through the day. It is not a zero-calorie diet or a primary weight-loss method, but a therapeutic approach, a cleansing on many levels, and an encounter with oneself.

Why fasting affects the metabolism

To understand why metabolic issues in particular are affected by fasting, it helps to look at what happens in the body. During fasting, it works on two levels simultaneously, which are often confused but should be distinguished.

The first level is fat burning. When readily available carbohydrate stores decrease, the metabolism switches from glucose to fatty acids and ketone bodies within the first few days. The body increasingly draws its energy from its own reserves. The second level is autophagy — the body's own recycling and cleaning processes at the cellular level, where cell components are broken down, utilized, and reorganized. To put it more elegantly: all recycling processes are activated, and everything is cleaned — cellularly, vascularly, in the connective tissue, in the gut, in the brain, and in the liver and kidneys. Both processes occur together, but they describe different mechanisms.

This transition explains why values related to metabolism shift during fasting. In the large observational study by Wilhelmi de Toledo et al., published in 2019 in PLOS One and conducted with 1,422 people fasting for four to twenty-one days, fasting blood glucose dropped significantly and averaged around 4.7 mmol/l, while ketone bodies, as a sign of fat burning, rose significantly. Such shifts are the reason why fasting is medically interesting for metabolic issues — though whether it is suitable in an individual case should always be discussed with the medical team at the Tannerhof.

Possible indications according to the guidelines for fasting therapy

The guidelines for fasting therapy come from the Ärztegesellschaft Heilfasten und Ernährung (ÄGHE), an association of physicians that provides a professional foundation for therapeutic fasting. First published in 2002 and updated in 2013, they describe the methodology, patient selection, contraindications, and medical supervision. On this basis — and supplemented by the experience of the medical team at the Tannerhof — the potential use of therapeutic fasting can be categorized for the following issues. Each of these statements is a professional assessment under medical supervision, not a promise of a cure:

• High blood pressure (hypertension). The guidelines cite blood pressure reduction through fasting in both overweight and non-overweight individuals with hypertension. In the PLOS ONE study, systolic blood pressure dropped on average from 131.6 to 120.7 mmHg, and diastolic from 83.7 to 77.9 mmHg.
• Metabolic syndrome and metabolic disorders. Obesity, high blood pressure, and lipid and glucose metabolism disorders are recognized as classic indications for fasting therapy.
• Type 2 diabetes mellitus. Fasting can favorably influence glucose metabolism; according to the ÄGHE, patients generally require no blood-sugar-lowering medication during fasting—making medical supervision and medication adjustment all the more essential.
• Rheumatic conditions. Several controlled trials have demonstrated marked symptom relief and a reduction in inflammatory markers in rheumatoid arthritis.
• Migraines. The ÄGHE points to studies showing that over 90 percent of patients experienced significantly fewer or no migraine attacks for at least six months following fasting therapy.
• Allergies, autoimmune diseases, asthma, and food intolerances. Here too, clinical studies on fasting therapy, accessible through the ÄGHE, indicate potential benefits.
• Depression and mood. An uplift in mood following fasting is well documented, explained neurochemically by changes in serotonin metabolism.
• Cancer in certain stages. Here, fasting is considered solely as a supportive (adjuvant) measure—never as a standalone or replacement treatment.

Weight loss should not be listed here as a primary treatment goal: in therapeutic fasting, it is a side effect that can only be sustained long-term with a follow-up strategy such as intermittent fasting or a low-carb diet.

What the studies actually show

A list of indications remains abstract as long as its reliability is unknown. Therefore, it is worth taking a closer look at the aforementioned observational study, which comprehensively documented the safety and efficacy profile of Buchinger fasting.

The study followed 1,422 people during fasting periods of four to twenty-one days using the Buchinger method. Of the participants who returned a self-report, 404 mentioned an existing health condition—and of these 404, 84.4 percent reported that their condition had improved significantly. No serious or lasting adverse effects occurred; physical and emotional well-being increased significantly in all groups. 93.2 percent of participants did not experience hunger.

Physical measurements can also be quantified. Depending on the duration of the fast, weight decreased by 3.2 kilograms (for five days) to 8.6 kilograms (for twenty days), and waist circumference by 4.6 to 8.8 centimeters. The following overview summarizes the key average values from the study:

It is important to put this into perspective: this is an observational study conducted under professional supervision, where participants were screened for contraindications beforehand. The figures describe what is possible under optimal conditions—they are not a guarantee for every individual. Providing this translation from study results to the individual case is exactly what the medical consultation is for.

Why medical supervision is crucial here

Especially when dealing with chronic and metabolic issues, medical supervision is not just an extra layer of safety; it is the core of the process. During fasting, the metabolism changes, and many medications—such as those for blood pressure, blood sugar, or coagulation—often need to be adjusted. A drop in blood pressure caused by fasting can mean that a previously appropriate dose is suddenly too high. Therefore, anyone taking medication should not fast without medical supervision. This is not an exclusion criterion, but rather the reason to place your fasting experience in expert hands.

At the Naturhotel Tannerhof, therapeutic fasting is always medically supervised—a philosophy that has grown over three generations of doctors. The doctors at the Tannerhof are experts in fasting; they monitor vital signs and circulation as well as the individual progress of each guest. It begins with the initial medical consultation on the first day of fasting, which is holistic in its approach: it includes a medical history, a physical examination—including bioimpedance analysis to measure body composition—and a review of current medications. It also covers the reasons for fasting, personal goals beyond the fast, and any previous fasting experience. Every person is different; the individual is at the center of everything we do. If necessary, follow-up medical consultations are provided, and the stay concludes with a final review to evaluate changes and discuss how to transition back into everyday life.

The length of stay is booked before arrival; during the initial consultation, the schedule can be coordinated within this timeframe and extended if health concerns require it. We are happy to dedicate more time to such concerns—ideally ten days of pure fasting or more, with close medical supervision.

More than just numbers: the supporting program

Fasting for health reasons involves more than just monitoring vital signs. The therapeutic program at the Tannerhof is intentionally broad because a week of fasting has an impact on many levels. Medical treatments include bioimpedance analysis, IHHT altitude training (depending on the program), and, where medically appropriate, ozone autohemotherapy. These are complemented by wraps and compresses, such as the liver-supporting hay flower wrap, aroma wraps, as well as mud and warm packs. We also offer baths and hydrotherapy, such as Kneipp contrast showers and magnesium-rich detox baths, alongside massages like the fasting massage, detox massage with royal oil, or acidosis massage, lymphatic drainage, and foot reflexology, supplemented by breathing therapy and sauna sessions. For the mental aspect, we offer psychotherapeutic coaching, nature coaching, business and communication coaching, and art therapy.

Movement remains an essential part of fasting, tailored in moderate doses: gentle base endurance training and light strength training are available alongside yoga, Feldenkrais, Tai Chi, and resistance band workouts. Summit hikes and running are entirely possible, provided the pace suits the fast—the body is drawing nourishment from within. The Tannerhof Spa, with its indoor pool, historic sauna hut, and BadeHarpfe bathhouse featuring a 25-meter outdoor natural pool opening up views between the Wendelstein and Sonnwendjoch peaks, is dedicated to tranquil moments in between. Above all lies this special setting: Bayrischzell, alpine meadows, mountain streams, and crisp, pure mountain air. My hideaway in the mountains is the sanctuary where fasting and medical guidance enhance one another.

Carrying the effect into everyday life

A week of fasting can trigger a lot—but it only has a lasting effect if your daily routine supports it afterward. This is especially true for metabolic issues, where diet has the greatest impact in everyday life. Which follow-up diet is appropriate is discussed in the final consultation with the attending physicians.

One path is Schlanke Tanne Low Carb, our proprietary low-carb dietary approach. It is not a replacement for Buchinger fasting, but rather a way to integrate the fasting experience into everyday life—featuring protein, vegetables, healthy fats, and the goal of eating differently without diminishing the joy of food. Focusing on heightened pleasure and zest for life rather than deprivation. Another path is intermittent fasting, such as a 16/8 rhythm: likewise not a replacement for Buchinger fasting, but the recommended method for carrying the benefits of periodic fasting sustainably into daily routines. This ensures that much of what the fasting week sets in motion endures well beyond your stay at the Tannerhof. An overview can be found in the Therapeutic Fasting and Schlanke Tanne hub.